A study of the "obesity paradox," which postulates that obese heart failure (HF) patients have a better chance of survival than normal-weight patients with HF, is specific to older individuals and those with decreased cardiac function without diabetes and with de novo HF, according to a study published Dec. 4 in the Journal of the American College of Cardiology.

The prospective, observational, global registry cohort study of 6,142 hospitalized acute decompensated HF patients reviewed the medical charts of a collection of 12 cohorts of patients with acute decompensated HF from Europe, North America, Asia and South America. It assessed all-cause mortality at 30 days and one year. The patients were stratified according to World Health Organization definitions of normal weight (body mass index [BMI] 18.5 to 25 kg/m²), overweight (BMI 25 to 30 kg/ m²), and obese (BMI ≥ 30 kg/ m²).

The study's investigators found that event-free survival was highest in obese individuals, followed by those who were overweight and then normal weight individuals at both 30 days and one year. Further, the protective association of higher BMI was particularly associated with individuals older than 75 years (p = 0.006), those with a left-ventricular (LV) ejection fraction of less than 50 percent and those without diabetes (p < 0.001). It was also associated with de novo HF patients diagnosed on hospital admission but not with patients with established chronic HF admitted with acute decompensation.

"We provide evidence for the existence of a global obesity paradox in acute decompensated HF, with a higher BMI associated with improved 30-day and one-year mortality around the world despite intercontinental heterogeneity in clinical and biochemical admission profiles, suggesting an association between mortality and BMI is robust," the study authors wrote.

They add that they demonstrated that "the association of BMI with outcome is specific to selected subgroups (non-diabetics, de novo HF diagnosis, HF with reduced LV ejection fraction)." Moving forward, the authors note "the clinical management of excess weight in patients hospitalized for acute decompensated HF needs specific tailoring at this sentinel stage in disease progression."

In an accompanying editorial, Ulrich Kintscher, MD, professor of Pharmacology and Metabolic Research at the Charité - Universitätsmedizin Berlin notes, "one of the most important questions remains: Do these findings translate into clinical or therapeutic practice? In the case of future confirmatory data, subgroup characterization should definitely determine future therapeutic approaches."

Keywords: North America, Overweight, South America, Disease-Free Survival, Europe, Registries, Body Mass Index, Heart Failure, Obesity, United States, Diabetes Mellitus, Disease Progression